Motor vehicles nowadays have an increasing number of electronically regulated systems. Monitoring is necessary in order to recognize possible malfunctions in such a system, for example in an engine controller. The purpose in this context is in particular to prevent safety-relevant instances such as unintended acceleration, unintended deceleration, or unintended transition to a standstill.
For such monitoring functions, for example, the malfunction of the engine controller can be detected on the basis of internal sensor information. This can be accomplished, for example, in a so-called three-level concept for the engine controller, in which internal vehicle variables are monitored. European Patent No. EP 1 485 598 B1, for example, describes the monitoring of a torque, and German Patent Application No. DE 10 2011 075 609 A1 describes the monitoring of an acceleration. The internal sensor information items or captured variables are plausibilized in this context.
Utilization of the internal information cannot, however, always reliably allow inference of a fault in the vehicle system. An example thereof is acceleration monitoring for the engine controller as described in German Patent Application No. DE 10 2011 075 609 A1. This monitoring function contains unknown environmental influences, for example wind or slope drag, that can distort vehicle-internal measurements of acceleration, i.e. exhibit a discrepancy between the target value and actual value. It is therefore not always possible to distinguish, on the basis of the acceleration signal, whether the detected faulty behavior allows inference of a fault in the system or of the unknown environmental conditions.
PCT Published Application No. WO 2008/141859 A2 describes, for example, a method in which a driving state of a motor vehicle, for example a transmission state of an automatic transmission, can be adjusted on the basis of environmental data such as travel route information. This does enable more efficient vehicle operation, but monitoring of a motor vehicle is not thereby possible.
It is therefore desirable to describe a maximally effective monitoring function for a motor vehicle with reference to motion variables, and to avoid the disadvantages of purely internal monitoring.